1). Field of the Invention
This invention relates to an image reading apparatus which is suitably applied to an image scanner and can be used to read an image in a facsimile or a like apparatus.
2). Description of the Related Art
In recent years, image reading apparatuses such as image scanners have been and are being developed in order to input image information to a computer or a like apparatus.
Such conventional image reading apparatuses, however, suffer from a reading speed which is not sufficiently high and the capacity for information (quantity of paper sheets) which can be read at a time is not sufficiently high. In order to solve this problem, not only is it necessary to improve the performance of an image reading mechanism itself which is a principal portion of an image reading apparatus, but it is also necessary to develop a mechanism which can accommodate a large number of paper sheets to be read therein and transport the paper sheets one-by-one with certainty. In particular, the sequence of operations of taking out paper sheets, which are accommodated in large numbers in a hopper and are subjected to reading, one-by-one with certainty, transporting the thus taken out paper sheets, reading the paper sheets during transportation and placing the paper sheets successively into a stacker, must be performed as rapidly and certainly as possible.
Further, also with regard to the paper size, it is desired that an image reading apparatus can feasibly handle paper sheets of various sizes from a small size to a large size.